I've done a lot of backpacking in my home state of Colorado. My pack and its contents is pretty light but not "ultralight", maybe 20 pounds including food.
I'm considering something like these for the Colorado Trail:
They are designed to be pulled by bikes but I think I could attach to my waist by straps. I don't have any physical limitations, I'm just intrigued by the possibility of leveraging the mechanical advantage of the wheel. And I wonder if this would classify as "mechanized" transport and thus not allowed in wilderness areas.